# crack up
## English
### Pronunciation

* IPA: /ˈkɹæk ˈʌp/
* Audio (General Australian):(file)

### Verb

crack up (third-person singular simple present cracks up, present participle cracking up, simple past and past participle cracked up)
* To laugh.
** (idiomatic, intransitive) To laugh heartily.
    It was hilarious. We were cracking up the whole time.
** (idiomatic, transitive) To cause to laugh heartily.
    The joke about the nuns in the bath cracked me up.
*** 2022 October 21, Jason Bailey, “How George Clooney and Julia Roberts Quietly Became the Tracy-Hepburn of Our Time”, in The New York Times‎:The joy of “Ticket to Paradise” comes not from its predictable plotting or razor-thin screenplay; it’s from watching them together, from observing how the sparks still fly, and (when the former flames get drunk and let their guards down, or during the end-credit outtakes) watching them crack each other up.
** (slang, intransitive) To tease (someone) or tell jokes at the expense of (someone).
    He's always cracking up at me about that.
* To break.
** (idiomatic, intransitive, dated in US) To become insane; to suffer a mental breakdown.
    She got through the war, but cracked up when her sister died.
*** 1936 February, F. Scott Fitzgerald, “The Crack-Up”, in Esquire‎:All rather inhuman and undernourished, isn’t it? Well, that, children, is the true sign of cracking up.
** (idiomatic) To break down or fall apart; to stop functioning; to shatter.
    The university was really cracking up, losing faculty, students and donors, and it seemed like to go under.
    My motorcycle cracked up before I arrived.
** (idiomatic, transitive) To separate a group.
    I have to crack up that little clique.
** (US) To crash an aircraft or automobile.
*** 1930 December, Lawrence M. Guyer, “Chuck Luck: The Story of a Flying Dog”, in Boys' Life:From all directions they came to the rescue, one predominant fear gripping their hearts: Fire! Someone had cracked-up. It was for this they sped. The flames that so frequently burst from a crashed airplane became an instantaneous cauldron; many a pilot has lived through the crash to die in the fire that followed.
*** 1983, John Thorn, David Reuther, The Armchair Aviator, page 101:When I reported this to Burwell by telephone, he called me a Chinese ace — in those days Chinese aces were pilots who cracked up their own airplanes […]
** (transitive) To remove the shell from nuts.
    We can send you a hundred pounds a month of pecans to crack up.
** (transitive) To crack (petroleum). (to break down (a complex molecule), especially with the application of heat: to pyrolyse)
    The refinery cracks up the heavier oils.
* To affect the image of something.
** (slang, transitive) To praise or applaud (something); to promote a positive view of (something).
    She wasn't as impressive as Katie cracked her up.
** (dated, transitive) To insult, demean or harm the image of (something).
    Those who have been cracking up the agricultural industry will hopefully reconsider their denigration of it.
** (transitive, informal, usually passive, usually negative) To cry up; to extol.
    This new computer system is not what it was cracked up to be.
*** 1939 June, George Orwell [pseudonym; Eric Arthur Blair], chapter IX, in Coming Up for Air, London: Martin Secker & Warburg, published 1948 (April 1959 printing), →OCLC, part II, page 132:No use, with a bloke like this, cracking up your own merits. Stick to the truth.
* (slang, intransitive) To smoke crack cocaine.
    I need to crack up.

#### Derived terms

* all it's cracked up to be

#### Translations
### Adjective

crack up (comparative more crack up, superlative most crack up)
* (New Zealand, colloquial) Funny; hilarious
    That joke was crack up.
** 2017 April 23, “McDonald's say 'neigh' to horses through the drive-thru”, in Stuff‎:"It was crack up!"
** 2020 April 20, “The curious case of a fictional spa in Westport”, in Newsroom‎:In town people would stop and say to me, “Hey Becky, that cat story was crack up.”
** 2020 June 5, “Police looking into footage of woman twerking on Auckland Harbour Bridge”, in Newshub‎, archived from the original on 20 September 2020:One person said it was "crack up", while the woman who uploaded it said "I'm a do it again (sic)".

### References

* ↑ “The Best 10 Kiwi Slang Words, Phrases and Kiwi-isms for International Students to Understand”, in IStudent‎, 2018 February 8

### Further reading

* “crack up”, in OneLook Dictionary Search.
* “crack”, in The Century Dictionary […], New York, N.Y.: The Century Co., 1911, →OCLC.